Disposable cartridge for admixing two components of injectable medicament

ABSTRACT

A cartridge unit for use in, or as a syringe, and comprising two chambers, each for containing a separate component of the final injectable mixture, wherein one of said chambers is detachably mounted on the unit, the other chamber is provided in the unit, and means are provided for communicating said two chambers and then causing the contents of the removable chamber to be introduced into the other chamber, whereafter the detachable chamber is removed to permit attachment of a push rod to the plunger or stopper when the unit is to be used.

0 United States Patent on 3,636,950 Gomez et al. 5 1 Jan. 25, 1972 [541DISPOSABLE CARTRIDGE FOR 2,726,656 l2/l955 Lockhart 1 28/272 x ADMIXINGTWO COMPONENTS OF 2,778,360 l/l957 Miskel .l28/2l8.l IN A 2,869,543l/l959 Ratcliffet al.... .....l28/2|8 M J C MENT 3,190,619 6/l965 Penneyet .....l28/272 X [72] Inventors: Eloy A. Gomez, Frazer; Stephen W.Good- 3,368,558 2/l968 Sarnoff et al. ..l28/2l8.l

sir, King of Prussia; Dominic A. Marrocco, Springfield, all of Pa.FOREIGN PATENTS OR APPLICATIONS 73 Assigneez American Home productsCorporation 577,6] 1 6/]933 Germany l 28/272 New York, 848.081 9/1952Germany ..l28/2l8 Filedl 1963 Primary Examiner-Joseph S. Reich [2| 1App, N03 775,726 Attorney-Andrew Kafko and Joseph Martin Wcignnm [57]ABSTRACT [52] U.S.Cl. ....l28/2l8 M, 128/218 D, 128/272 51 lm. CI...A61m 05/00 A cam'dge "1". [58] Field of Search 128/2"; 218 M 218 N 218NV chambers, each for containing a separate component of the finalinjectable mixture, wherein one of said chambers is 128/2181 218'] 218218 218 P detachably mounted on the unit, the other chamber is providedin the unit, and means are provided for communicating [56] Reerencescued said two chambers and then causing the contents of the UNITEDSTATES PATENTS removable chamber to be introduced into the otherchamber, whereafter the detachable chamber is removed to permit at-3,489,147 1/1970 Shaw 128/218 M tachmem f h d to the lunger or stopperwhen the unit 1,557,836 lO/l925 Hein ..128/220 ism be l,799,463 4/1931Hein.... ....l28/22O 2,671,449 3/1954 Dann ....l28/218 N 7 Claims, 5Drawing Figures 20 I4 1 l c i I "l 2 l; l! l l2 I8 17 20 IS -v J g 4bml? |4a- DISPOSABLE CARTRIDGE FOR ADMIXING TWO COMPONENTS OF INJECTABLEMEDICAMENT.

BACKGROUND OF THE INVENTION This invention relates generally tohypodermic syringes, and more particularly to a cartridge unit,ampule-needle assembly, or the like, adapted for admixing two differentcomponents contained separately in sealed compartments thereof prior touse, whereby a sterile therapeutic mixture or composition may beinjected as desired.

In many instances, it is necessary that, preparatory to inject ingcertain therapeutic mixtures or compositions, the different componentsthereof, which may be unstable when mixed, are maintained separatelyuntil used. In other instances, it is necessary to reconstitute a drug,which is preferably stored in dry form, by dissolving or suspending itin a liquid medium.

Conventional devices for accomplishing the foregoing purposes usuallyinclude at least two separate compartments, each of which contains oneof the components of the therapeutic composition. Just before injectionof the therapeutic composition comprising the mixed components is to bemade with the device, said components are admixed in situ. Obviously,such mixing must be done in a sterile manner without loss of eithercomponent to assure the required proportions, and hence, potency of themedicament to be in' jected. This is usually accomplished by one of anumber of generally known expedients. For example, the mixing may bebrought about (a) by at least partially removing a common wall orpartition provided between two chambers, each containing one of thecomponents; e.g., as disclosed in U.S. Pat. No. 2,636,493 and U.S. Pat.No. 2,766,766; (b) by the breaking of a separating wall or membrane uponapplication of hydrostatic pressure; e.g., as in U.S. Pat. No. 3,351,058and U.S. Pat. No. 2,708,438; or (c) by elaborate valving arrangements',e.g., as disclosed in U.S. Pat. No. 3,326,2l5 and U.S. Pat. No.2,665,687; and also (d) by providing for the piercing of achamber-separating wall or membrane by a cannula needle; e.g., as inU.S. Pat. No. 3,098,483 and U.S. Pat. No. 3,327,710. Generally, suchdevices of the various types exemplified in said patents are eithercomplicated in structure, bulky, cumbrous and/or do not permit facileattachment of a push rod to the stopper or plunger of the cartridge unitat the time of use.

SUMMARY OF THE INVENTION In view of the foregoing, it is an object ofthe present invention to provide a new and improved cartridge unit forcontaining two separate components in two separate compartments toassure that there is no mixing together of said components until thedesired time.

It is another object of the present invention to provide a cartridgeunit possessing the desired advantages of segregated storage, mixing andinjection capability.

A further object of the invention is to provide a new and improvedcartridge unit of the type described, wherein the separate componentsare initially maintained in separately sealed chambers and may berapidly and thoroughly mixed together at the desired time withoutexposing the chambers externally, thus eliminating the possibility ofspillage or contamination of the components both before and aftermixing.

Another object of the invention is to provide such a car tridge unitwherein one chamber thereof may be detachably mounted on the unit,whereby, after the contents thereof is transferred to the chamber whichis permanently provided in the unit, said one chamber may be removed topermit insertion of the unit into a syringe and attachment of theplunger rod of the latter to the stopper of the unit, which may then beused for injection.

It is another object of the present invention to provide such acartridge unit which may be used in a syringe or as a fully disposablesyringe per se.

It is yet another object of the invention to provide such a cartridgeunit wherein commercially available ampule-needle LII assembliescomprising a single chamber for medicament may readily be modified toobtain the two chambered mixing structure of the invention.

Still another object of the invention is to provide such a cartridgeunit wherein, subsequent to the mixing operation, the modifyingstructure is removable, whereby a commercially available ampule-needleassembly may then be used in its usual manner.

It is another object of the present invention to provide such acartridge unit wherein at least one wall of the detachably mountedchamber thereof is formed of a flexible material so that when pressureis applied thereto (:i.e., when the internal volume is decreased bycompressing said one wall) the removable chamber is caused first tocommunicate with the second chamber containing a second component of thecomposition, and thereafter, the component in the removable chamber iscaused to be transferred to said second chamber.

The foregoing, and other features, objects and advantages of the presentinvention are attained by the provision of a new and improved cartridgeunit wherein there is provided a rigid tubular member forming the mainbody of the assembly and providing a first chamber having a distalclosed end and a proximal open end. A reciprocable stopper is positionedin said tubular member and seals off a. portion of the first chamberincluding the distal end thereof. In a preferred embodiment of theinvention, a stud is anchored in the stopper and extends axially thereofwith a. portion protruding therefrom toward the proximal end of thefirst chamber and the distal end directed towards a penetrable area ofthe stopper. The stud has an axial channel extending completelytherethrough wherein there is positioned, for axial movement therein, acannula, which has a piercing point at either end, and is hereinafterreferred to as a double-pointed cannula. The double-pointed cannula hasthe distal end thereof located adjacent the penetrable area of thestopper. The cannula has a laterally projecting element affixed theretoat the proximal end thereof which is normally positioned proximally awayfrom the proximal end of the stud and is adapted to limit the distalmovement of the cannula in the: axial chamber upon abutment of thelaterally projecting element with the transverse web ofthe distal endofa mounting bushing. The mounting bushing is removably positioned inthe proximal end of the rigid tubular body and has an aperture in saidweb thereof through which the stud protrudes. Associated with theaperture are connecting means for removably attaching the bushing to thestud, thereby to prevent undesired movement of the plunger when thechamber is depressed. Preferably, such connecting means comprise a malescrew thread on the proximal end of the stud and a complementary femalescrew thread in the aperture in the web of the bushing.

Positioned in the mounting bushing, which functions as a housingtherefor, is a movable sack providing a sealed chamber and having atleast one wall thereof which may move inwardly of the sack to reduce thevolume of the chamber pro vided thereby. The distal wall of the sack isof a penetrable material, and when the sack is positioned in themounting bushing, said wall overlies the proximal end of thedoublepointed cannula.

In a preferred embodiment of the invention, the wall of penetrablematerial is faced, at least in part, with a rigid portion whichfunctions to limit the distal travel of the sack in the bushing when thelaterally projecting element of the cannula and/or proximal edge of thestud in the stopper is abutted by said rigid portion. Preferably, themounting bushing is pro vided at its proximal end with a lateralprojection extending outwardly of the tubular body when mounted thereinand functioning as a finger rest, only during premanipulation of thecartridge unit for the mixing operation as will appear hereinafter.

In another embodiment of the invention, the stud in the plunger isomitted and, instead, the plunger is provided with an axially disposedbore extending from the proximal surface of the plunger to a point closeto but not through the distal surface thereof. The bore is provided witha female screw thread. The bushing, instead of having an apertureprovided with a female screw thread, has a proximally disposed nipplehaving an axial bore completely therethrough adapted to receive thedistal end of the double-pointed cannula. The outer surface of thenipple is provided with a male screw thread complementary to the femalescrew thread of the bore of the plunger, whereby the bushing may beremovably connected to the plunger. In this embodiment, the removablesack is preferably provided with a neck at the distal end in which thereis an axial bore, in this case, extending through the distal surface ofthe neck but terminating at the proximal end thereof, which is closed bya transverse web of penetrable material functioning as a seal for thechamber in the removable sack. The bore has a diameter to permitreciprocation therein of a piston permanently affixed to the proximalregion of the double-pointed cannula. The distal end of the bore has arestriction therein defining a reduced diameter which permitsreciprocation of the double-pointed cannula therethrough but functionsas a stop for the piston affixed thereto, thus limiting distalreciprocation of the cannula-piston assembly. Reciprocation of saidassembly in the proximal direction is limited by abutment of the pistonwith the proximal transverse web of the bore, after the proximal end ofthe double-pointed cannula has penetrated said web.

The nature of the invention will more readily appear on a reading of thedescriptions of several preferred embodiments thereof set forth below,with reference to the drawings wherein:

FIG. 1 is a side elevational view ofa cartridge unit assembly embodyingthe invention, with portions of the structure broken away to disclosethe contents of the sack and tubular barrel and the interior structuresof the ferrule and cannula assembly;

FIG. 2 is an exploded view of the proximal portion of the assemblyillustrated in FIG. I; I

FIG. 3 is an axial cross section of the assembly shown in FIG. 1, takenon line 3-3 thereof;

FIG. 4 is a side elevational view of a modification of the unit of FIGS.1-3, wherein the sack, cannula, and bushing assembly is omitted, andinstead, there is a removable cover positioned in the proximal open endof the unit, and a dual purpose cannula guard and push rod is attachedto the distal end of the unit; and

FIG. 5 is a vertical cross section of the proximal end of the unitdisclosed in FIG. 4, with the cover removed and a bushing and modifiedsack and needle assembly inserted therein.

Referring now to the drawings, and particularly FIGS. 1, 2, and 3, thecartridge unit disclosed therein comprises a tubular barrel 2 to whichis affixed, on a distal neck 2a thereof, a plastic ferrule or hub 3 anda metal injection cannula 4. As will be recognized by those skilled inthe art, ferrule 2 may, alternatively, be of metal, as is conventionaland shown, for example, in U.S. Pat. No. 2,671,450. Cannula 4 isprovided with a removable cannula sheath 5 of rubber which isfrictionally mounted on a distal portion 3a of ferrule 3, to encasecannula 4, as also appears in said patent.

Sealingly mounted within barrel 2, but reciprocally movable therein, isa resilient plunger or stopper 7 having a stud 8 anchored axiallytherein with the proximal end 9 thereof protruding from said plunger 7.Said stud 8 has a male screw thread 9a thereon adapted for selectiveattachment thereto of a plunger rod ofa syringe, not shown, but whichmay be or" the structure disclosed, for example, in U.S. Pat. No.2,671,450. Tubular barrel 2 per se, the plunger 7 therein, and neck 2aat the distal end of barrel 2, enclose a first chamber It) in which maybe contained the first component 40, which may be a solid or liquid, ofthe medicament.

Positioned in the proximal end 2!) of tubular barrel 2 is a bushing 14of plastic. Bushing 14 has, at the distal end thereof, a transverse web14a within which is centrally provided a female-threaded aperture 141)of a diameter to permit attachment of said bushing 14 screw threadedlyon the complementary male thread 9a provided on the proximal end 9 ofstud 8, as best seen in FIG. 3. The proximal portion 14c of bushing I4is of a larger diameter than the remainder thereof and is connected tothe latter by an annular extension I5 which functions as a limiting stopwith respect to the insertion of bushing 14 in barrel 2 upon abutment ofsaid extension IS with the edge 2c of the proximal end 2!; of barrel 2.Annular extension 15 serves also as a finger rest when the device isbeing utilized in the mixing operation, as referred to in greater detailhereinafter.

In accordance with this preferred embodiment of the present invention,stud 8 has an axial bore I] completely therethrough. Positioned forreciprocation in said bore I I is a double-pointed cannula 12. Asassembled (i.e., prior to use of the device in the mixing operation) andas appears in FIG. 3, the distal end 12a of cannula I2 is positionedadjacent a pierceable area 7a located at the distal end of plunger 7.The proximal end 12!) of the double-pointed cannula I2, on the otherhand, protrudes beyond the proximal end 9 of stud 8 and hence withinbushing 14 when the latter is attached to stud 8. At said proximal end12b, cannula 12 has axially affixed thereto a laterally projecting disk13, which is positioned proximally of web 14a of bushing 14. Thediameter of disk I3, as shown, is greater than that of the centrallylocated aperture 14b in web 14a of bushing 14 and substantially that ofthe interior of bushing 14 for purposes which will also appearhereinafter.

Positioned in bushing 14 is a sack 16 which encloses a second chamber I7containing a second component 42, which may be a solid or a liquid, ofthe medicament to be mixed with the first component 40 in the firstchamber 10. Sack I6 is provided with a distal surface 18, which, in thisinstance has been sealed at reentrant area after the liquid has beenintroduced into chamber 17. Said area 18a is penetrable by the proximalend 12b of double-pointed cannula 12, as referred to hereinafter.

Sack I6 is provided at the proximal region of its circumferentialsurface with bellows folds 20, whereby, upon suitable pressure on theproximal end 16a of sack I6, said region may be collapsed, thereby toreduce the volume of the second chamber 17 provided therein whichcontains the second component 42.

In the assembly of the conventional cartridge portion of the embodimentof the invention just described, plastic ferrule 3 and metal cannula 4may be permanently mounted on the distal neck end 2a of the tubularbarrel 2, as described, for example, in U.S. Pat. No. 3,278,357. Cannula4 may be provided with a cannula sheath 5, manually, or by a devicedescribed, for example, in U.S. Pat. No. 3,188,727. Thereafter, thefirst component 40 of the medicament is introduced into first chamber 10in barrel 2, and plunger 7 may be inserted into barrel 2 by apparatusdescribed, for example, in Serial No. 5 I 3,l36 filed Dec. l0, I965,which has matured into U.S. Pat. No. 3,39l,5l8.

Alternatively, if desired, ferrule 3 may be of metal and attached, withthe cannula affixed thereto previously to barrel 2, by apparatusdescribed, for example, in U.S. Pat. No. 3,247,64l. In this alternativeassembly, the procedural steps are quite different. Thus, the plunger 7is inserted first; then, with the tubular barrel 2 inverted so that theopen end thereof faces upwardly, the contents of the first chamber 10may be introduced, and thereafter the assembly consisting of ferrule 3and cannula 4 may be crimpingly attached to the tubular barrel 2, as bysaid apparatus of U.S. Pat. No. 3,247,641.

As will appear to those skilled in the art, the modes of the assembly ofthe parts described immediately above form no part of the presentinvention, and may be varied as found desirable.

Reverting now to the assembly of the above desired embodiment of themixing structure of the present invention, doublepointed cannula 12,with disk 13 affixed thereto, is first inserted via the open proximalend of bushing 14 into the distal region thereof. Disk 13 riding withinbushing 14 functions as positioning means for double-pointed cannula 12so that the distal end 112a of the latter protrudes through aperture 14bin web 14a of bushing l4, while the proximal end I217 of cannula 12 withthe disk l3 affixed thereto is positioned within the distal end ofbushing 14. Thereafter, sack 116, which already contains the secondcomponent 42 of the medicament sealed in the second chamber 17 thereofas referred to before, is introduced into said bushing 14, whereby thesurface 18 of sack 16 faces distally towards the proximal end of webII4a of bushing I4, but is spaced therefrom to avoid penetratingabutment of penetrable area 13a with the distal end 112!) ofdoublepointed cannula 12, for a purpose which will also appearpresently.

As part of the assembly of this embodiment of this invention, bushing14, with double-pointed cannula l2 and sack 16 positioned therein asjust described, is next inserted into the proximal end 2b of barrel 2.As the distal end of said assembly is inserted into barrel 2,double'pointed cannula I2 is main tained in position by disk 13 bearingwithin bushing 14 so that distal end I211 of double'pointed cannula 12is aligned with bore 111 of stud It and enters said bore. Said assemblyis inserted further into barrel 2 until the portion of web 14a ofbushing l4 which surrounds screw-threaded aperture 14!; thereof abutsthe proximal edge 9 of stud 8. Bushing I4 is then rotated for screwthreadedly attaching it to stud t by means of said screw-threadedaperture 14!) and complementary male screw thread 9a of stud 8. Rotationof bushing I4 is continued until annular extension thereof abuts edge 2cof tubular barrel 2. In such arrangement of the parts, double-pointedcannula I2 is positioned within bore ll of stud 8 with the distal end12a thereof located adjacent penetrable area 7a of plunger 7, andplunger 7 is retained against any inadvertent reciprocal movement.

Just prior to the use of the device by the doctor, nurse, or other partyperforming the injection of medicament into the patient, sack 16 may beurged distally in bushing l4, until area 18a of sack l6 abuts theproximal end 12b of double-pointed cannula l2 and begins to urge itdistally in bore 1] of stud 8 until the distal end 12a of doublepointedcannula I2 abuts area 7a of plunger 7. As sack 16 is urged furtherdistally in bushing 14, and depending upon the relative pcnetrabilitycharacteristics of area 18a and 70, first one and then the other of saidareas is penetrated by the respective ends 1212 and 12a ofdouble-pointed cannula 12. As will be understood, during theseoperations, plunger 7 is maintained substantially in the position shownin FIG. 3, because of the attachment of stud 8 thereof to bushing 14 asdescribed above.

Regardless of the sequence of penetration, when sack 16 is ultimatelypressed home within bushing 14, area Ida of sack I6 is fully pierced bythe proximal end 12b of double-pointed cannula l2, area 7a of plunger 7is fully pierced by the distal end 12a of double-pointed cannula I2, andthe laterally projecting disk III on double-pointed cannula I2 isabutted on its proximal surface, by the distal surface of web 18 of sackl6, and on its distal surface by the proximal end 9 of stud 8. In suchrelationship of parts, said first chamber W in tubular barre] 2 is incommunication with second chamber ll7 in sack l6 via double-pointedcannula l2.

Finger pressure is next applied to proximal end 16a of sack 16 to reducethe volume of second chamber 17 therein and hence to force the secondcomponent 42 thereof through double-pointcd cannula 12 into firstchamber It) in tubular barrel 2 containing the first component 40 of themedicament. The entire device may be shaken manually or otherwiseagitated to cause appropriate mixing of the second component 42 with thefirst component 40 in chamber 10.

Subsequently to the mixing operation, bushing 14 is unscrewed from stud8, and thereafter is lifted out of the proximal end 212 of tubularbarrel 2, to carry therewith both sack 16 and double-pointed cannula 12.

At the time of use for actual injection, the cartridge unit comprisingtubular barrel 2, ferrule 3, cannula 4, cannula sheath 5, plunger 7, andthe mixed medicament in chamber l0, may simply be inserted into asyringe of the type described in US. Pat. No. 2,671,450, referred tohereinbelow and the plunger pushrod of said syringe screw threadedlyattached to stud 8 of plunger 7. Thereafter, as is conventional, cannulasheath 5 may be removed to uncover cannula 4 and the device utilized forthe usual injecting operation, including aspiration, as desired.

In the embodiment of the invention disclosed in FIGS. 4-5, the barrel,ferrule and cannula structures are substantially identical to those ofthe embodiment disclosed in FIGS. 1-3, with the exceptions notedhereinafter. Accordingly, said substantially identical structures inFIGS. 45 are indicated by the same, but primed reference numerals. Thestructural and operational differences of the embodiment of FIGS. 4-5when compared with that of FIGS. I-3 will appear from the followingdescription of the former.

As disclosed in FIG. 4, a cannula guard 6 is mounted on ferrule 3' (FIG.5) by means of the male screw thread 3b on the latter and acomplementary female screw thread within a first bore (neither of whichscrew thread or bore is visible in FIG. 4) in the proximal end 6a ofcannula guard 6, thereby to cover the cannula sheath 5 of cannula 4'(FIG. 5). The general relationship of the cannula guard 6 to theremaining structure described hereinbefore is conventional and isdisclosed in detail, for example, in US. Pat. No. 2,671,449. The singlenotable exception to the cannula guard 6 structure shown in said patentis that, in the present instance, instead of there being provided in thedistal end of said guard 6 a second bore having a female screw threadtherein adapted for attachment to a stud on the plunger 7', there isprovided, on said distal end of guard 6, a nipple 6b having a male screwthread 6c thereon for a purpose which will later appear.

A further and more important distinction of the FIGS. 4-5 embodimentfrom that depicted in FIG. I-3 is that, in the former, the plunger 7',the bushing 14', the sack l6, and the double-pointed cannula 12 havemodified structures now described.

Primarily, plunger 7' is not provided with a stud. Instead, plunger 7 isprovided with an axial bore 28, in which is a female screw thread 29.The latter is complementary to the male screw thread 6c on nipple 6b ofcannula guard 6. However, the distal end of bore 28 is closed by apenetrable area 7a of plunger 7'. Bushing 14 does comprise an annular extension I5 at its proximal end. However, at its distal end, it is notprovided with a female threaded aperture 14!) in transverse web ll4'athereof. Instead web l4a is provided with a distally disposed nipple 30which has axially therethrough a bore 30a and, on its peripheralsurface, a male screw thread 30b. Male screw thread 30b is alsocomplementary to female screw thread 29 of bore 28, whereby nipple 30may be removably attached to plunger 7 as shown in FIG. 5.

Mounted in bushing 14' is a sack 16 which, in this instance, has thegeneral configuration of an inverted plastic bottle, the neck 16'!) ofwhich is provided with an axial bore 24. Sack l6 encloses a chamber l7which contains the second component 42 of the medicament to be injected.Bore 24, at its proximal end is separated from chamber 17' ofsack l6 bya penetrable web ll8'a. At the distal end of bore 24, there is affixed arestriction cap Zll which defines a smaller diameter opening 31 throughwhich double-pointed cannula l2 reciprocates. Affixed adjacent to theproximal end l2b of cannula I2 is a piston 13 which is reciprocablymounted within bore 24. As will be apparent from FIG. 5, piston I3functions as a stop which limits reciprocation of double-pointed cannulal2 distally when said piston 13' engages with web l8a, and proximallyupon engagement of piston l3 with restriction cap 211.

In the assembly of sack 16 per se, the chamber 17' of the latter isfilled with the second component 42 and sealed. Double-pointed cannula12 with piston 13 affixed is next inserted in bore 24 of neck ll6'b.Thereafter, restriction cap 21 is pressed over distal end ll2'a ofcannula I2 and sealed to the distal end of neck 1612.

As a further distinction of this modified embodiment of the invention,bushing 14, sack 16, and cannula 12' may be provided to the ultimateuser as a unit assembly separately of the cartridge unit comprisingtubular barrel 2, stopper 7', ferrule 3', cannula 4', sheath 5', andguard 6. in such case, the distal end l2'b protruding from bore 30:: innipple 30 of bushing 14' may be covered by a cap (not shown) removablymounted on nipple 30 by means of a complementary female screw thread,

and sack 16' may be paper or plastic sealed (not shown) in bushing 14'.Also for purposes of sterility, there is provided in the proximal end 2bof tubular barrel 2, a removable cover 51 which is frictionally seatedin the proximal end 2b of barrel 2, as shown in FIG. 4. Cover 51 has aperipheral lip 51a overlying edge 2c of barrel 2, which edge, in thiscase, is in the form of a bead 2d. The latter functions to retain anannular finger piece 52, in a manner also disclosed in said US. Pat. No.2,671,449.

In the use of the embodiment disclosed in FIGS. 45, cover 51 is removedfrom tubular barrel 2'; the cap, if provided on nipple 30 of bushing 14is removed to expose the distal end l2'a of cannula 12; and, again ifprovided, the seal of the sack 16 to the bushing 14 is broken.Thereafter, the user inserts the aforesaid unit assembly of bushing 14',sack l6 and dou ble-pointed cannula 12 into the proximal end 2b ofbarrel 2' and then screws nipple 30 of bushing 14' into the bore 28 ofplunger 7 by means of the complementary screw threads 30b and 29,respectively (FIG. 5).

In the mixing operation, the sequence of manipulation is generallysimilar to that described with respect to the embodiment in F108. 1-3.Specifically, the sack 16 is first pressed home in bushing 14 untildouble-pointed cannula l2 penetrates both web l8a of sack l6 and thepenetrable area 7a of plunger 7'. Thereafter, pressure on (or squeezingof) the distal end l6a of sack l6 forces the first component 40 inchamber 17' thereof through double-pointed cannula l2 and into chamberin tubular barrel 2 containing the second component 42 of themedicament. As in the previous embodiment, mixing as by agitation may beundertaken, followed then by removal of the bushing 14, sack l6, anddoublepointed cannula l2 assembly by first unscrewing nipple 30 ofbushing 14 from bore 28 in plunger 7' and thereafter lifting said entireassembly out of barrel 2 as a unit.

In the ultimate use of this embodiment of the invention for hypodermicinjection, cannula guard 6 is unscrewed from ferrule 3' to expose sheath5 which covers cannula 4 (as shown in FIG. 5). Cannula guard 6 is thenattached toplunger 7 by means of the complementary screw-threaded nipple6b of the former and bore 28 of the latter. With the parts in suchassembly. cannula sheath 5 may be removed to expose cannula 4 and thecartridge unit used as a completely disposable syringe per se byutilizing the finger piece 52 in grasping barrel 2 while the thumb ofthe user is positioned on the proximal end 60 of cannula guard 6 whichnow functions as a push rod in the manner described in the aforesaid US.Pat. No. 2,671 ,449.

It will, of course, be understood that, although two specific andpreferred embodiments of the invention have been described above indetail, many changes and modifications may be made, and said inventionembodies in widely differing forms, without departing from the spiritand scope thereof, in its broader aspects coming within the language orscope of any one or more of the appended claims. Merely by way ofexample, the several parts may be made of various materials, such asglass, plastics, rubber or metal as desired; other ferrule-cannulaassemblies may be utilized, or omitted; other finger piece, cannulasheath and/or guard assemblies may be employed, or omitted; the screwthreads may be replaced by other connecting means, such as bayonet, balland socket, or other frictional attachment means; the double-endedcannula may be provided with stop means other than the disc and pistonshown; the bushing and the sack may be provided with complementary screwthreads whereby the sack may be screwed into the bushing rather thanpushed thereinto; the sack may be rigid and be provided with othervolume reducing means, such as a piston; etc. Other variations,including interchange of specific element structures and/or assemblies,in the embodiments disclosed, will suggest themselves to those skilledin the art,

We claim:

1. A cartridge unit assembly adapted for selectively maintainingseparately or admixing two components of a medicament composition, saidassembly comprising:

a. a rigid tubular member forming the main body of said assembly andproviding a first chamber adapted to contain a first component of amedicament and having a distal closed end and a proximal open end;

b. a reciprocable stopper, having a peripheral surface and positioned insaid tubular member and sealing a portion of said first chamberincluding said proximal end thereof, said stopper having an axial boretherein extending inward from the proximal region of said stopper andbeing closed by a penetrable area in the distal region thereof;

. a bushing, means mounting said bushing in said proximal open end ofsaid tubular member, said bushing having an opening at its proximal endand having a transverse web at its distal end provided with a centrallylocated aperture therein;

d. a sack reciprocably mounted in said bushing and having a portionthereof extending from the proximal end of said bushing, said sackdefining a second chamber adapted to contain a second component of amedicament, having a penetrable membrane closing the distal regionthereof, and being provided with means for ejecting the contents of saidsecond chamber;

e. a double-pointed cannula mounted in said bushing and having theproximal end thereof extending proximally interiorly of said bushing andterminating adjacent said penetrable area of said sack, and having thedistal end thereof extending distally within said axial bore in saidstopper and terminating adjacent the penetrable distal area of saidstopper, said double-pointed cannula having stop means affixed theretoand positioned interiorly of said bushing, first and second abutmentmeans mounted in said bushing distally and proximally of said stopmeans, respectively, for limiting both distal and proximal reciprocationof said double-pointed cannula within said bore of said stopper uponengagement of said stop means with said first and second abutment means,respectively, said first and second abutment means retaining said stopmeans within said bushing;

. complementary connecting means provided in said bore in said stopperand on said transverse web of said bushing for removable attaching saidbushing to said stopper.

2. A cartridge unit assembly as defined in claim I, wherein said sack isprovided with a resiliently collapsible wall.

3. A cartridge unit assembly as defined in claim 1, wherein stop meansare provided on said bushing for abutment with the proximal end of saidmember for limiting distal entry of said bushing in said member.

4. A cartridge unit assembly as defined in claim 1, wherein saidconnecting means comprise:

a stud which is mounted in said stopper, has an axial bore therethrough,and has a male screw thread on at least the proximal region thereof, and

said centrally located aperture of said bushing has a female screwthread therein.

5. A cartridge unit assembly as defined in claim 1, wherein said firstabutment means comprises a stud mounted in said stopper and said secondabutment means comprises the distal end of said sack, and wherein saidstop means affixed to said double-pointed cannula abuts, in the extremedistal reciprocation of said double-pointed cannula, with the proximalend of said stud mounted in said stopper and in the extreme proximalreciprocation of said double-pointed cannula, with the distal end ofsaid sack.

6. A cartridge unit assembly as defined in claim 1, wherein saidconnecting means comprises a female screw-threaded bore in said stopperand a male screw-threaded nipple of said bore, and wherein said secondabutment means comprises said penetrable membrane of said sack whichcloses the proximal end of said bore, and said piston abuts, in theextreme distal reciprocation of said double-pointed cannula, with saidrestriction means, and in the extreme proximal reciprocation of saiddouble-pointed cannula, with said penetrable membrane of said sack.

1. A cartridge unit assembly adapted for selectively maintaining separately or admixing two components of a medicament composition, said assembly comprising: a. a rigid tubular member forming the main body of said assembly and providing a first chamber adapted to contain a first component of a medicament and having a distal closed end and a proximal open end; b. a reciprocable stopper, having a peripheral surface and positioned in said tubular member and sealing a portion of said first chamber including said proximal end thereof, said stopper having an axial bore therein extending inward from the proximal region of said stopper and being closed by a penetrable area in the distal region thereof; c. a bushing, means mounting said bushing in said proximal open end of said tubular member, said bushing having an opening at its proximal end and having a transverse web at its distal end provided with a centrally located aperture therein; d. a sack reciprocably mounted in said bushing and having a portion thereof extending from the proximal end of said bushing, said sack defining a second chamber adapted to contain a second component of a medicament, having a penetrable membrane closing the distal region thereof, and being provided with means for ejecting the contents of said second chamber; e. a double-pointed cannula mounted in said bushing and having the proximal end thereof extending proximally interiorly of said bushing and terminating adjacent said penetrable area of said sack, and having the distal end thereof extending distally within said axial bore in said stopper and terminating adjacent the penetrable distal area of said stopper, said double-pointed cannula having stop means affixed thereto and positioned interiorly of said bushing, first and second abutment means mounted in said bushing distally and proximally of said stop means, respectively, for limiting both distal and proximal reciprocation of said double-pointed cannula within said bore of said stopper upon engagement of said stop means with said first and second abutment means, respectively, said first and second abutment means retaining said stop means within said bushing; f. complementary connecting means provided in said bore in said stopper and on said transverse web of said bushing for removable attaching said bushing to said stopper.
 2. A cartridge unit assembly as defined in claim 1, wherein said sack is provided with a resiliently collapsible wall.
 3. A cartridge unit assembly as defined in claim 1, wherein stop means are provided on said bushing for abutment with the proximal end of said member for limiting distal entry of said bushing in said member.
 4. A cartridge unit assembly as defined in claim 1, wherein said connecting means comprise: a stud which is mounted in said stopper, has an axial bore therethrough, and has a male screw thread on at least the proximal region thereof, and said centrally located aperture of said bushing has a female screw thread therein.
 5. A cartridge unit assembly as defined in claim 1, wherein said first abutment means comprises a stud mounted in said stopper and said second abutment means comprises the distal end of said sack, and wherein said stop means affixed to said double-pointed cannula abuts, in the extreme distal reciprocation of said double-pointed cannula, with the proximal end of said stud mounted in said stopper and in the extreme proximal reciprocation of said double-pointed cannula, with the distal end of said sack.
 6. A cartridge unit assembly as defined in claim 1, wherein said connecting means comprises a female screw-threaded bore in said stopper and a male screw-threaded nipple mounted on said bushing, said nipple having an axial bore therethrough communicating with said centrally located aperture in said bushing.
 7. A cartridge unit assembly as definEd in claim 6, wherein said cannula stop means comprises a piston affixed to said double-pointed cannula reciprocably mounted in a distally located axial bore in said sack, and wherein said first abutment means comprises restriction means located in the distal region of said bore, and wherein said second abutment means comprises said penetrable membrane of said sack which closes the proximal end of said bore, and said piston abuts, in the extreme distal reciprocation of said double-pointed cannula, with said restriction means, and in the extreme proximal reciprocation of said double-pointed cannula, with said penetrable membrane of said sack. 